Concrete stair



Jan. 11 1927. 1,613,774 A. E. SHLAGER ET AL CONCRETE STAIR Filed July 6. 1925 IN VEN TOR.

BYYSMW 1 ATTORNEY.

Patented Jan. 11, 1927.

UNITED STATES PATENT OFFICE;

ABRAHAM E. SHL'AGEB AND BENNETT M. GROISSER, OF BOSTON, MASSACHUSETTS.

CONCRETE STAIR.

Application filed July 6, 1925.

' Our invention relates to stairs whose treads are filled with a concrete mixture. Stairs whose treads are filled with concrete have atendency to crack after they have been in use a certain length of time. In order to overcome this objection, iron rods are usually imbedded within the concrete.

The object of our invention is to provide a stair whose tread will not crack on continued use and whose risers will be maintained in their original position.

Another object of our invention is to provide an arrangement by which the risers are held securely in place and the concrete filler on the stair is strengthened and prevented from splitting, or cracking.

The invention will be hereinafter considered in detail and specifically claimed. Reference will now be had to the drawing forming a part of this application, wherein there is illustrated a preferred embodiment of our invention but it is understood that the elements thereof can be varied or changed as for shape, size or form without departing from the spirit of the invention.

In the drawings Fig. 1 is a section through the stair show ing the tread and the means of re-enforcing and strengthening the tread.

Fig. 2 is a section through the stairs showing the tread and riser.

Fig. 3 is an enlarged view of the connection member shown in Fig. 1.

1* 1g. 4 is an end view or the same member.

1 and 2 designate two 11'011 stringers which are used as the two sides of a stair to which are fastened the connecting members 3 and shy means of bolts 5 and 6. The connecting members 3 and at have vertical extenslons 7 and 8.

Serial No. 41,719.

The riser 13 carries an extension let which is connected through the tread of the next step by bolt 15 and fo ms a channel or receptacle 16, as shown in Fig. 2, into which the concrete is poured.

A flat iron plate 12 has slots on each end corresponding to the extensions 7 and 8 which pass through the slots in the iron plate 12 and are connected by the iron rod 9 and fastened together by means of nuts 10 and 11. The iron plate 12 is integral with the riser 13 and forms the base of the tread. I The rod 9 acts both as a means to hold the stringers together and as a re-enforcement for the tread. This re-enforcement prevents the concrete treads from cracking.

The lower extension 17 of the connecting members 3 and 4: may extend upward and parallel to extensions 7 and 8, so that the bolts 5 and 6 are imbedded in the concrete.

Having described our invention, what we claim is 1. A stair comprising spaced stringers, angle members connected to said stringers and provided with extensions, a plate supported by said angle members and adapted to carry a layer of concrete, and means embedded in said concrete and secured to said extensions whereby to connect said stringers and reinforce said concrete.

2. A stair consisting of two stringers to which there are connected two angular members; said members being provided with extensions; a flat plate with openings therein corresponding to the said extensions titted 7 over the extensions; andabarconnectingthe said-members and being completely imbedded in a layer of concrete.

' ABRAHAM E. SHLAGER.

1 BENNETT M. GROISSER. 

